1. Field of the Invention
The present invention is directed to an elastic clutch of disk design used in conjunction with a split flywheel for an internal combustion engine, and, more particularly, to an elastic clutch of disk design having a plurality of elastic clutch elements respectively disposed within a plurality of cutouts formed in the circumference of the split flywheel.
2. Description of the Related Art
Elastic clutches of disk design used in conjunction with a split flywheel for an internal combustion engine are known in the art, e.g., DE-PS 36 35 043. Such clutches segregate the rotational vibrations of the internal combustion engine from the drive train connected thereto. The elastic clutch elements of the clutch may be formed having suitable elastic properties so as to have an effect on the operating and resonance performance of the entire drive train. The elastic clutch elements, which preferably are fashioned as helical springs, serve primarily to transfer the torque of the internal combustion engine to the drive train.
Congested installation conditions in modern drive trains and the tendency for internal combustion engines to have ever higher engine torques mandates optimal utilization of the space available for the clutch; this in turn requires accommodating a maximum spring volume within a minimum space.
One approach for maximizing the spring volume within a given design space is to arrange the helical springs within one another in a nested fashion. This approach has proven satisfactory in the dampers of classic clutch disks since relatively short springs are used with such clutches.
Long helical springs, which are preferably used in an engine having a split flywheel, display a much more unfavorable wear performance than the relatively short springs used in classic clutch disks. The unfavorable spring wear makes it necessary to use a more expensive spring guide, especially if the springs operate dry or with poor lubrication.
DE-PS 36 35 043 and DE-PS 39 16 575, both of which are incorporated herein by reference, disclose helical spring guides for individual helical springs which reduce the possibility of buckling of the springs under centrifugal force and may consist of selected materials forming a suitable pairing with the helical springs. Such spring guides minimize the spring wear and increase the fatigue strength of the clutch.
What is needed in the art is a spring guide for nested helical springs which substantially prevents the helical springs from touching one another and minimizes the wear of the helical springs and spring guide.